Benign tumors of the chorioidea

Benign tumors of the choroid are rare and include hemangioma, osteoma, and fibrous histiocytoma.

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Choroidal hemangioma

Choroidal hemangioma is a rare congenital tumor, related to hamartomas. It is detected accidentally or with visual impairment. Decreased vision is one of the early symptoms of a growing hemangioma in adults; in childhood, strabismus is the first to attract attention. In the choroid, a hemangioma almost always looks like an isolated node with fairly clear boundaries, round or oval in shape, the maximum tumor diameter is 3-15 mm. Tumor prominence varies from 1 to 6 mm. Usually, the color of the tumor is pale gray or yellowish-pink, it can be intensely red. Secondary retinal detachment, its folding are observed in almost all patients; with large tumors, it becomes vesicular. The caliber of the retinal vessels, unlike that in choroidal melanoma, does not change, but small hemorrhages can form on the surface of the tumor. With weakly expressed subretinal exudate, cystic retinal dystrophy creates a picture of the "openwork" of the tumor.

Diagnosis of cavernous choroidal hemangioma is difficult. Discrepancies between clinical data and histological examination results are observed in 18.5% of cases. In recent years, the diagnosis has become more reliable due to the use of fluorescent angiography. Treatment was long considered futile. Currently, laser coagulation or brachytherapy (contact irradiation with radioactive ophthalmic applicators) are used. Resorption of subretinal fluid helps reduce retinal detachment and improve visual acuity. The prognosis for life is favorable, but vision in untreated hemangioma or in the absence of treatment effect may be irreversibly lost as a result of total retinal detachment. In some cases, total detachment ends in secondary glaucoma.

Pigmented choroidal tumors

The source of pigment tumors is melanocytes (pigment-producing cells), which are distributed in the stroma of the iris and ciliary body, as well as in the choroid. The degree of melanocyte pigmentation varies. Uveal melanocytes begin to produce pigment at a late stage of embryonic development.

Choroidal nevus

Choroidal nevus is the most common benign intraocular tumor, localized in the posterior part of the fundus in almost 90% of cases. Ophthalmoscopy reveals nevi in 1-2% of the adult population. There is reason to believe that the frequency of nevi is actually much higher, since some of them do not contain pigment. Most nevi are congenital, but their pigmentation appears much later, and these tumors are discovered by chance after 30 years. On the fundus, they look like flat or slightly protruding foci (up to 1 mm high) of light gray or gray-green color with feathery, but clear borders, their diameter varies from 1 to 6 mm. Amepiform nevi have an oval or round shape, their borders are smoother, but less clear due to the absence of pigment. Single drusen of the vitreous plate are found in 80% of patients. As the nevus grows, dystrophic changes in the pigment epithelium increase, which leads to the appearance of a larger number of vitreous plate drusen and subretinal exudate, a yellowish halo appears around the nevus. The color of the nevus becomes more intense, the borders become less clear. The described picture indicates the progression of the nevus.

Patients with stationary nevi do not require treatment, but they need dispensary observation, since during life the tumors can grow, turning into a stage of progressive nevus and even initial melanoma. Progressive nevi, taking into account the potential possibility of their degeneration and transition to melanoma, are subject to treatment. The most effective method of destroying a progressive nevus is laser coagulation. With a stationary nevus, the prognosis for both vision and life is good. Progressive nevus should be considered as a potentially malignant tumor. There is an opinion that 1.6% of nevi necessarily degenerate into melanoma. As a rule, up to 10% of nevi, the diameter of which is more than 6.5 mm and the height is more than 3 mm, become malignant.

Choroidal melanocytoma

Choroidal melanocytoma is a large-cell nevus with a benign course, usually localized on the optic nerve head, but can also be located in other parts of the choroid. The tumor is asymptomatic, and in 90% of patients it is detected by chance. With large melanocytomas, minor visual impairment and an increase in the blind spot may be noted. The tumor is a single node, it is flat or slightly protruding (1-2 mm), the boundaries are quite clear. The size and localization are different, but most often melanocytoma is located near the optic nerve head, covering one of its quadrants. The color of the tumor in most patients is intensely black, on the surface there may be light foci - drusen of the vitreous plate.

Treatment is not required, but patients should be under systematic observation by an ophthalmologist. In the stationary state of the tumor, the prognosis for vision and life is good.